//
// Created by dw on 2021/8/12.
//
#include <iostream>

using namespace std;

template<class T>
T Sum(T a[], int n) {
  if (n > 0) {
    return Sum(a, n - 1) + a[n - 1];
  }
  return 0;
}
int main(int argc, char **argv) {
  int a[] = {1, 3, 5, 7, 9, 11, 13, 15, 17, 19};
  cout << Sum(a, 10) << endl;
  return 0;
}
